A longstanding goal of the Laboratory has been to determine the effect of age, gender, cardiovascular (CV) disease, and lifestyle variables on cardiac performance, both at rest and during exhaustive dynamic exercise. To accomplish this mission, we have utilized several techniques including gated cardiac blood pool scanning, Doppler echocardigraphy, and measurement of maximal aerobic capacity (VO2max). These studies are predominantly focused on the Baltimore Longtiudinal Study of Aging (BLSA), a panel of about 1000 community dwelling volunteers ages 20 to over 90 years. Recent examples of these studies are shown. A. To determine whether the beneficial effects of exercise training on CV performance in older individuals depend on the baseline fitness level, we performed rest and maximal exercise gated radionuclide ventriculography in 10 sedentary men aged 60 plus minus 2 years before and after 6 months of aerobic exercise training and in 8 endurance trained men of similar age before and after detraining for 12 weeks. At peak cycle exercise after the intervention, all of the initial intergroup differences in CV performance were abolished, indicating that CV performance in older adults is modulated inlarge part by physical conditioning status. B. To determine the relationship between left ventricular (LV) filling variables and LV structure, we performed by Doppler echocardiography, in 289 healthy, normotensive subjects age 20-89 yr (mean 52[unreadable]18) from the Baltimore Longitudinal Study of Aging. Age-associated decreases in peak E and E/A ratio and increases in LV mass index, relative wall thickness (RWT), the ratio of LV diastolic wall thickness to cavity size, peak A, atria filling fraction (AFF) and isovolumic relaxation time (r=0.28), each p<.0001, were observed. By multiple regression analysis, independent determinants of reduced E/A ratio were age (p<.0001), systolic blood pressure (SBP, p<.01) and heart rate (p<.001). AFF was directly related to age (p<.0001), SBP (p<.02) and RWT (p=.05). Neither LV mass index, cavity size or posterior or inraventricular septal wall thickness was an independent predictor of E/A ratio or AFF. Thus, age-associated changes in diastolic LV performance are not primarly determined by the modes LV Hypertrophy which accompanies normative aging.